Automatic signaling mechanism for schools



E. R. MERCER AUTOMATIC SIGNALING MECHANISM FOR SCHOOLS July 4, 1933.

Filed May .28, 1952 3 Sheets-Sheet l c I I July 4, 1933. E. R. MERCERAUTOMATIC SIGNALING MECHANISM FOR SCHOOLS Filed May 28, 1932 5Sheets-Sheet 2 y 4, 1933- E. R. MERCER 1,916,769

AUTOMATIC SIGNALING MECHANISM FOR SCHOOLS Filed May 28, 1932 5Sheets-Sheet 3 934 WWW U Figure 1 Patented July 4,. 1933 UNITED STATES ij i 1,915,7 9"

.snwann MERGER, or eInBoN, NEBRASKA Annemarie SIGNALING iiEcHnivIsi/iron SCHOOLS Application filed May 28,

This invention relates to means for auto matically sounding audiblesignals used in schools for the purpose of indicatingclass' periodsandthe general object of this invention is to provide av mechanism of thischaracter which'can be applied to and used with almost any i'ionstrikingclock.

A further object is to provide a structure of this character which,while particularly designed for use in schools, can be applied tovarious other systems of signals for other purposes. r

A further object is to provide a structure of this character which isrelatively simple, can be easily adapted to special uses, and which ispositive and certain in its operation.

Other objects will appear in the course of the following description.

hly invention is illustrated in the accomianying drawings, wh reinFigure 1 is a front elevation of a signal ing mechanism combined withthe clock, the signalingniechanism being constructed in accordance withmy invention;

.Figure 2 is a section on the Figure 1;

Figure 3 is a Figure 1;

Figure 1 is a line 22 of section onthe line 33 of sectioi'i on. the line1l of Figure 5 is a section on the line 55 of Figure 1; a i

F i ure 6 1s a fra mentar detailed elevas 4 tion of the contacting.fingers, the contact carrying wheel and allied parts;

Figure 7 1s a fragmentary section on the line 7-7 of Figure 6 throughthe contact wheel and the insulating bar supporting the contact fingers;

F1gure8 is a section on the llne 88 of.

' Figure 4;

Figure 9 is a fragmentary elevation of the ratchet wheel and the meansfor driving it; Figure 10 is a section on the line 1010 of Figure 1; v

Figure 11 is a fragmentary sectional view through the supporting shaftof the contact wheel and through a portion of the-frame. Referringparticularly to Figui-e 1, 10 des ignates the frame of an ordinarynon-strikesz. Serial No. 614,183. I y ingi'clock having an hour hand 11and a minutehand 12. The gearing whereby this clock is driven-and thespring are not shown inasmuch as these parts are of the ordinary andusual construction. it he hour hand is J5 driven by the gear wheel 13en'gaging'with the usual pinion 14;. So far the construction is thatcommonly found in clocks. My attachment includes, the supporting frame15 upon which is mounted the shaft l6'carrying upon it the toothed wheel17 which engages with the pinion 14. Thus this toothed wheel is drivenfrom the pinion. I

Mounted upon the face of the toothed wheel are a plurality of lugs 18,whichlugs are riveted, bolted or otherwise attached to v the wheel as at19 so that the lugs may be shifted" somewhat tofproperly adjust them.Pivotally mountedupon a, shaft20 above the wheel 17 is a downwardlyextending curved finger 21 against which the lugsl18 successively strikeas the wheel 17 moves in the direction of the arrow in Figure 1. Alsomounted upon this shaft. 20 and operating in 21 is the straightconjunction with .the finger arm 22. Pivoted upon a shaft 23 -is anangular arm'24, theangular extremity .of which extends over the arm 22.This shaft carries upon it the upwardly bowed arm 25 which at itsextremity is connected to a link 26 which in turn is connected to aplunger 27 or weight. When a lug 18 strikes the finger 21- it will liftthis finger and 'coincidently lift the arm 22, which. will lift up .onthe arm 24, causing the raising of the plunger weight 27 and as thefinger 21 passes over the lug 18 and is released thereby, the plungerwill drop. I have illustrated eight of these lugs V 18 but as many oftheselugs may be used as desired and preferably the lugs are curved uponthat face which strikes the finger 2l so as to readily lift it or exerta wedging effect upon this finger. y

The plunger weight 27 operates freely throughthe guides 28 attachedtothe frame This fralne is "provided with lugs 29 whereby the frame maybe supported on the same base as the clock frame 10. Pivotally supportedbelow the weight 27- is a lever 30 O pivoted at 31, one end of thislever projecting into the path of movement of the weight 27 so thatwhen'this weight 27 is allowed to drop, the rear end of the lever willbe raised. A spring 32 acts to urge the weight engaging end of the leverupward. To the opposite end of the lever is connected a link 33.

Mounted upon a frame 34 disposed downward and to the right of the frame15 is a detent 35 to which the lower end of the link 33 is pivotallyconnected. The free end of this detent 35 is formed with a hook-shapedor angular portion 36 which extends into a notch in one of the gearwheels of the signal controlling mechanism. lever 35 is pivotallymounted upon a shaft 37 and also mounted upon this shaft for coincidentmovement with the detent 35 is the stop arm 38 which is slightly curvedor hookedat its extremity. Also mounted upon this shaft 37 forcoincidentmovement with lifting arm 39, the free end of which is somewhat curvedtoward the parts 35 and 38 is a the extremity ofthe arm 38. Rotatablymounted upon the frame 34 is a shaft 40. One end of this shaft rotatesin a fixed hub or shaft section 400 rivetedto. the frame 34a and thusheld from rotation. Loosely mounted upon. this shaft section 40a (seeFigure 11) and ,insulated therefrom is a ratchet wheel. 41 formed with arelatively deep notch 42, within which the angular. extremity of thedetent 35 normally engages. Alsomounted upon the same shaft 40, astheratchet wheel 41 is a toothed wheel 43. For the purpose This shaft isdriven by the spring 45, one end of which is attached to the shaft andthe other end of which is rigidly engaged with the frame 34 as at 46.Mounted upon the shaft 44,is the toothedwheel 47 and also mounted uponthe shaft 44 is the ratchet wheel 48. The wheel 47 is loose upon theshaft 44 but is rotated therewith in the direction of the arrow bymeans. of the ratchet wheel 48 and a pawl 49 mounted upon the wheel 47.This permits the spring to be wound up from time to time. 'The wheel'47engages a lantern wheel or pinion 50a mounted upon a shaft 50 carrying agearwheel 51, this wheel 51 engaging a pmlon on the shaft 40 and thusdriving this shaft 40 and driving the wheel 43.

The wheel engages with the lantern wheel or pinion 52 mounted upon ashaft 53, this shaft carrying upon it the, gear wheed 54. This gearwheel engages with the lantern wheel or pinion 55 mounted upon agovernor shaft 56. The governor shaft carries upon it the dislr 55carrying the two governor arms 58 pivoted thereto and weighted at theirouter ends so that as the speed increases the arms will swing outwardunder centrifugal force. The arms 58 have angular extensions 59, whichbear against a washer or disk 60 loosely surrounding the governor shaftin The outer end. of the I provide a shaft 44.

turn bearing against a coiled compression spring 61 mounted upon thegovernor shaft. The outer end of plurality of friction disks 62 which inturn bear against the outer element 34a of the frame 34. This is mostclearly shown in Figure 3. Obviously as the speed increases the frictiondisks will act as a brake and thus the movement of the train of gearingwill be kept uniform and constant at all times. I may say thatl havetriedthe use of the usual flutter wheel for the purpose of controllingthe action of the clock movement but have found that the flutter wheelis entirely too uncertain in its action and that it is necessaryto use agovernor in order to secure the certainty of regulation which thegovernor supplies.

It will be seen that I have described means for driving the controllingwheel 17 which controls the operation of the detent 35 and that I havedescribed means whereby the signal controlling wheel 41 may be operatedwhen released by the detent 35.

The means for causing the sounding of a signal or signals ata-predetermined time is as follows v Mounted uponthe wheel41. are a pairof contacts 63 and 63a disposed relatively closely together (see Figureand disposed in spaced relation to this pair of contacts is a contact64. The contact 63 and the Contact 64 are disposed so as to projectoutward from the surface of thewheel 41 as shown clearly in Figure 7. '1

Mounted upon a transverse bar 65 of insulating material as shown inFigure 7 are a pair of contact fingers 66 which are so adjusted that thetips of these fingers will just touch the contacts 63 but not touch thewheel 41. These contact fingers at their rear ends; are connected to abinding screw 67 having the usual binding nut 68' thereon. An adjustingscrew 69 is provided whereby the fingers may be adjusted so as tobring'their tips in exactly the position to just touch the upper edgesof the contacts 63. From one of the contacts 66, a conductor 70 extendsto a battery 71 or other source of current and to the bell or other poleof this signalthe conductor 73 extends toabinding post 74 carried by thebar 65. From the other contact 66 a conductor 75 extends which includesa source of current 7 6, a bell 77 and a return conductor 78 coming backto the'binding post 74. Thus itwill be seen that each time the fingers66' wipe across a contact 63 or the contact 64, a circuit will be closedthrough these bells or other sig nals 72 and 77. I

For the purpose of lifting the arm 25 'so as to prevent the actuation ofthe lever 30 and the release of the wheel 41, I have provided thevertical rod 79 which at its upper end is formed with the arm 80 whichengages this SDIIIIO' bears a ainst a signal 72. From the other Figure6.

beneath the arm as shown in Figure 1, the lower end of this arm 79 beingconn-ectedto an angular lever 81 pivoted at 82 and opcrating over anotched bar88.

This bar on opposite ends is notched to engage out of the notches andwhen the lever is turned to the right in Figure 1, the mechanism isoperated or on. When the lever is turned to the left hand end of the bar83, the mechanism is inoff position. As before stated, the wheel 41 isloose uponthe shaft and is entirely insulated from the shaft. This wheel41 is given a step by step movement by means of aninsulated pin 84carried by the lantern wheel or pinion 52. It is to be understood thatthis pin 84 is to be entirely insulated from the pinion 52in anysuitable manner. It will be seen that with this construction, the wheel41 is rotated one step upon each complete rotation of the wheel 54 andthat the wheel 41 is electrically engaged by contact finger 85 whichextends from the binding post 74 as shown most clearly in V The wheel 54with its shaft 53 and, of course, all the train of gearing connectedthereto and driven by themotor spring is normallyhcld from rotation bythe arm 38 which at its end is hook-shaped and engaged with the stop pin86 carried by the wheel 54.

Projecting from the wheel 54 is a pin 87 which coacts with the curvedarm 39 to lift the arm 38 from engagement with the pin 86 and hold thedetent 36 off of the wheel 41 while the pin 84 is engaging the ratchetteeth of wheel 41. This curved arms!) lifts the detent on arm 36 out ofthe ,(leep notch 42 and also lifts this detent over each cog as thewheel is being moved one cog at atime. When the detent 86 lands betweenthe teeth on the rim of the wheel, pin 86 fails toengagc with the hookedend of the arm /Vhen I pin 8'? comes up under the curved .arm 39, lift-sthis curved arm n award and while the.

dctent 36 is above the teeth, the pin 84 which constitutes a tooth movesinto the space between the teeth on wheel 41 and moves this wheel.another notch.

This movement continues until the deep notch 42 comes opposite thedetent 86 where? upon thedetent drops into this deep notch and at thesame time the hooked end of the arm 38 moves into position in front ofthe allow the phimger 27 enough slack to trip the detent 35 when thelever 30 is struck by the plunger. Furthermore, the straight arm 22 thislever 81 which may be sprung 1ng arm suficiently to stop the plungerfrom. striking the leve130 when the plunger drops; This happens when thecut-out lever 81 is placed at its oil position. It will-be obvious thatthe lever 81 can be turned to off or on position at any time during theday oiflii'ight without interfering with 'the correct ringing orrequiring the apparatus to be reset. You can thus cut it out at 1: 30 P.M., leave it until 4:00 P. M., throw the lever 81 back to on and it willring the 4: 08 bell just the same.

It will be seen that by changing the position of the lugs on thecontrolling wheel which operates the dropping of the weight or plunger,the bells may be caused to'ring at any desired intervals of time and itis obvious that these lugs might be made adjustable around the wheel soas to adapt the mechanism to any desired cycle of operations.

It will be seen that normally the contact fingers are disposed betweenthe contacts on the contact wheel, as shownin Figure 6, and that almostimmediately after the plunger drops, the fingers engage the firstcontact of the series and ring the bells that two minutes afterwards thefingers engage the second contact of the series and ring a second belland that three minutes after this, a third or final bell rings.

The lugs 18 represent a forty-five minute schedule and can be rotated oroscillated to vary the time of tripping several minutes earlier or lateras the case requires. WVith this construction these lugs are knife edgedand thus the time can be regulated to the sec ond. T

One of my objects in using the weight or plunger 27 to release thedetent 36 is that the action. is very quick and decided as it is only amatter of releasing this plunger and the tripping of this switch may beaccomplished very quickly and very closely for the reasons above stated.Furthermore, by pro,- viding this releasable plunger, I can provide verysimple means whereby the plunger may be shown lifted, so that itstripping finger n will be entirely out of the path of movement of thetripping finger 22.

o By using the twenty-four hour wheel as a I control element in thisdevice, I eliminate any chance for the schedule to be thrown oil orinterrupted in actual usage if the clock is kept running on time. I doaway with any necessity of resetting the ringing mechanism after cuttingoil for Saturday and Sunday of each week. Ringing on schedule will startat the exact time each day and will be kept up without further attentionand winding the clock. r

It will be obvious that any number of bells or other signals may beoperated by means of this mechanism or that as before described, themechanism may be prevented from operating by the shifting of the leverto its off position.

1. A time controlled switch including a contact wheel, a motor therefor,fixed con tact fingers coacting with the contacts on the wheel, a detentholding the contact wheel and the motor from operation, and clockactuated means for momentarily lifting said detent andthen permittingthe detent to again detainingly engage with the contact wheel after thecontact wheel has made one complete revolution.

2. A time controlled switch including a contact wheel, a motor, gearingconnecting the motor to the contact wheel and including a pinionengaging the contactwheel and giving it a step by step movement in onedirection, the contact wheel'having a plurality of contacts thereon,contact fingers engageable. with said contacts, a detent normallyholding the contact wheel from operation and holding the motor operatedgears from opera-- tion, and clock actuated means for momentarilyraising said detent out of engagement with the contact wheel to permitthe contact wheel to make one full revolution, the detent after suchfull revolution of the contact wheel then detainingly engaging thecontact wheel and stopping the action of the motor operated train ofgears.

3. A time controlled switch including a contactwheel having a pair ofcontacts disposed in close relation to each other, and a contactangularly spaced from the firstnamed contacts, a pair of fixed contactfingers adapted to be engaged byv said contacts successively as thewheel is rotated, a motor, a train of gears driven by said motor andincluding a gear element giving a step by step rotation to the contactwheel, a detent engaging the contact wheel and when engaged with thecontact wheel impeding the operation of the train of gears, clockactuated means for momentarily lifting said detent to permit therotation of the contact wheel from said motor operated train of gears,and means for holding said detent out of operative engagement with thecontact wheel u'ntilthe con tact wheel has made one complete rotationand the fingers are disposed between the first named pair of contactsand out of engage ment with either. 1

4. A time controlled switch including a contact wheel having aplurality-of contacts thereon, a motor, a train of gearing between themotor and the contact wheel to cause the rotation of the contact wheel,a contact finger. engaging successively with the contacts on the wheel,a detent normally preventing the rotation of the contact wheel, andclock actuated means for lifting said detent including a lever connectedat one end to said detent, a plunger disposed to engage said lever whendropped, a clock. actuatedwheel, and means on said wheel for preventingthe rotation of the contact wheel,

and clock actuated means for lifting said detent including a leverconnected at one end to said detent, a plunger disposed to engage saidlever when dropped, a clock actuated wheel, and, means on said clockactuated wheel for dropping said plunger at predeterm ned times to thuscause the retraction of the detent, including lugs on the wheel disposedat spaced intervals, a lifting arm for the plunger, and means actuatedby said lugs for raising the lifting arm and then dropping it.

6. A time controlled switch including a contact wheel having a pluralityof contacts thereon, a motor, a train of gearing between the motor andthe contact wheel. to cause the rotation of the contact wheel, a contactfinger engaging successively with the contacts on the wheel, a detentnormally preventing therotation of the contact wheel, clock actuatedmeans for lifting said detent including a lever connectedat one end tosaid detent, a plunger disposed to engage said leverwhen dropped, aclock actuated wheel, and means on said clock-actuated wheel for raisingand successively releasing said plunger at predetermined times to thuscause the retraction of the detent, including lugs on the wheel.disposed at spaced intervals, a lifting arm for the plunger, a doublearmed lever having one of its arms extending into the path of movementof the lug, a double-armed lever having one of its arms connected to theplunger, the other arm of the first named lever engaging beneath thesecond arm of the second-named lever whereby to cause the lifting ofthe-plunger as the first'uiamed arm is struck by a lug and the droppingof the plunger when the firstnamed arm escapes from a lug.

7. A time controlled switch including a contact wheelhaving a pluralityof contacts thereon, a motor, a train of gearing between the motor andthe contact wheel to cause the rotation of the contact wheel, a contactfinger engaging successively with the contacts on the wheel, a detentnormally preventing the rotation of the contact wheel, clock actuatedmeans for lifting said detent including a lever connected at one end tosaid detent, a,

plunger disposed to engage said lever when dropped, a clock actuatedwheel, means on said wheel for raising and then successively releasingsaid plunger at predetermined times to thus cause the retraction of thedetent, including lugs on the wheel disposed at spaced intervals, alifting arm for the plunger, a double-armed lever having one of its armsextending into the path of movement of the lug, a double-armed leverhaving one of its arms connected to the plunger, the other armof thefirst-named lever engaging beneath the second arm of the second-namedlever whereby to cause the lifting of the plunger as the first-named armis struck by a lug and the dropping of the plunger when the first-namedarm escapes from a lug, and means for holding the plungcr raisedcomprising a rod having a hook engaging beneath the plunger, and amanually operable lever shiftable to raise or lower said hook.

8. A time controlled swi ch of the character described, including acontact wheel having ratchet teeth and carrying a plurality of contacts,a pair of contact fingers engageable with said contacts, the contactwheel having a detent receiving notch, a spring motor, a train of earingoperatively connected to the motor to be driven thereby, a governoroperatively engaged by the train of gearing to control its movement, thetrain of gearing including a wheel, a one-toothed pinion carried by thewheel and engaging a ratchet tooth on the contact wheel once upon eachcomplete rotation of the pinion, a pivoted detent having an angular endnormally disposed in said notch of the contact wheel,

two arms carried by said detent and movable therewith, one of said armshaving a hooked extremity, the last named gear wheel having a stopengaged by the hooked arm when the detent is in said notch, a second armcarried by the detent and having a curved end portion and a pin carriedby the gear wheel and. engaging said last-named arm when the tooth onthe pinion is about to engage a ratchet tooth to cause the lifting ofthe detent above the teeth of the contact wheel.

9. In a time controlled switch. mechanism of the character described, aninsulated metallic contact wheel having thereon a pair of radiallydisposed metallic contacts projecting from one surface thereof and dis-'posed closely contiguous to each other, and having thereon a contactspaced a predetermined distance from the first named pair of contacts, apair of metallic contact fingers mounted opposite said face and.engaging the crests of the metallic contacts on the wheel, clockcontrolled means causing the complete rotation of the contact wheel atpredetermined 1 intervals, and manually operable means for controllingthe rotation of the contact wheel.

10. A time controlled switch mechanism including a supporting frame, awheel carried by the frame and engageable with the driving pinion forthe hour hand of a clock, the wheel having a plurality of lugs spaced atpredetermined intervals upon one face, a weighted plunger mounted uponthe frame, means engaged at intervals by said lugs lifting said plungerand then dropping it, a motor driven contact wheel having spacedcontacts thereon, contact fingers engageable with said contacts, adetent for preventing the rotation of said wheel, and means actuatedby adropping of the plunger for lifting said detent and holding it lifteduntil the contact wheel has made a complete revolution.

1'! including a contact wheel carrying a pinrality of contacts, motorcontrolled means for-driving said contact wheel, a contact fingerdisposed to be engaged by said contacts of the contact wheel, a detentnormally holding the contact wheel from operation under the action ofsaid motor, clock actuated means acting to momentarily lift the detentfrom its detaining engagement with the wheel to.

permit the actuation of the wheel, means aclng automatically to shiftthe detent to a position where it will not prevent the move ment of'thecontact wheel nder the action of the motor until said wheel has made onecomplete revolution, and manually operable means for preventing therelease of said de-v tent by the clock actuated mechanism,

In testimony whereof I hereunto afiix my signature.

EDWARD R. MERCER.

A time controlled switch mechanism

